It has been a part of the prior art to facilitate the preparation of food in the kitchen in such manner that products are offered to the housewife already prepared and ready for cooking. Products of this type which have been known the longest are noodles and dried soups.
Formerly the noodles were prepared fresh from wheat farina or flour and eggs, and the drying of the goods was made only for the requirement of a short time period.
Through mass manufacture, namely through the shaping and drying of the noodles, they merely need to be placed into boiling water by the consumer, as a result of which the noodles will be ready for consumption after a longer or shorter period of cooking.
Dried soups which are ready for cooking, and which have no fixed shape and therefore are in the form of a powder, require a somewhat more cumbersome preparation since they have to be stirred at first or made into a dough before they can be placed into boiling water.
During the past few years, dried preparations or dried products have increased greatly, from which the housewife can produce dumplings. These known preparations made mainly from raw or boiled potatoes represent, of course, a great relief for the housewife in comparison to the preparation of dumplings in the household which had been customary heretofore. Nevertheless, even in the case of these dried preparations, a number of steps are required in the household to obtain potato products such as dumplings. The preparation time is also considerably longer than in the case of the above-mentioned products.
The natural fresh potato, during preparation in the kitchen shows, in the form in which it can be consumed, considerable variations, depending on the process used. If the potato as a whole is boiled in water, then the starch granules will swell in the preserved cell bonds. The water from the cells that can be filtered away and that becomes visible after cutting the raw potato seems to have disappeared and was used up for the maximum swelling of the starch granules inside the cell, If however, the raw potato is comminuted, then one will obtain a thin, pasty mixture of individual exposed starch granules, cell fragments and fibers, as well as free liquid from the tissue. If this watery mash is heated to cooking temperature, then one will obtain a gluetinous tough product, which differs completely from a whole boiled potato in its physical nature and its organoleptic structure, although in both cases all the substances of the potato are present in the same quantitative composition.
Thus, it is apparent that the shape, appearance, structure and taste of the prepared product depend upon in what state the potato starch is available after preparation. The starch can be in its native state outside the cell bond. The starch can furthermore be swelled outside the cell; it can be swelled inside the cell and it can be unswelled inside the cell. Each of these four main states of appearance of the starch results in structural differences in the finished product. Several processes have been known in the prior art to obtain durable products from dried potatoes. These processes are discussed below in terms of three principal types of processes.
In a first process type, larger pieces of potatoes in the form of slices, cubes, chips, etc., are dried. The initial material is the whole potato. After peeling, the potatoes are cut to the desired shape (slices, cubes, pegs, chips) while interpolating a blanching step, and are subjected subsequently to a drying process, typically on trays, belts or vacuum drums. These products result, after "reconstitution" while absorbing water and subsequent or simultaneous heating, in sliced or cubed potatoes, potato pegs or chips, which in their shape resemble the products prior to drying. Only after cooking are they in a consumable state. When observing their fine microscopic structure, one can recognize that the large majority of the starch grains lie within the cells and that the starch similarly as in the case of a freshly boiled potato has a maximum swelling. The individual cells show the original, undistrubed cellular bond which is injured and disturbed only at the cuts. Here, quantities of starch have emerged from the cells and are glued together outside the cells.
The second process type of the durable dried potato products starts out from mashed potatoes. In this case, the potato, after paring, is not only blanched but it is heated, with the cell bonds intact, up to the maximum swelling of the grains of starch. Subsequently, the potato is transformed in a fine mash in different ways. The mash, in the ideal case, is a so-called unicellular mash, i.e., each cell lies by itself, but the still unhurt cellular membrane encloses the grain of starch swelled to the maximum. This mash is dried either on a roller drier, a vacuum drier or a spray drier.
When drying on a roller drier, one will obtain bright yellow, dilute homogenous flakes which after dissolution in hot water or milk result in a loose potato puree. While drying in the vacuum or when spraying one will obtain a powdery product from the original mashed potatoes, which after mixing with hot water or milk again results in a potato puree.
These dried products may be changed into porous granules, with accelerates dissolution again to a potato puree after addition of hot water or milk in the sense of an instantaneous effect. In any case, after "reconstitution" the well known, typical potato puree develops.
Microscopically, the roller dried flakes as well as the powder and the granulate consist of individual cells with swelled starch.
The swelling of the starch proceeds to the point of gluing together. When observed with a polarization microscope, the double refraction phenomenon with the characteristic spherical cross is omitted. The individual grains of starch are greatly swelled and in most cases considerably deformed. If such a preparation is dyed, the individual swelled areas of the grains of starch can be recognized separated from one another. The tissue bonds have dissolved for the great part into individual cells. Groups of cells with a common cell wall consisting of two to four cells are rare. The individuals cells are from round to oval; the outside surfaces of the cell fragments are rounded. In the dry flakes, the rounded surfaces of the cells with their points of contact adhere to one another. After addition of water during reconstitution, the individual cells separate from one another, so that a unicellular puree in there again.
More recently, a third, basic process has been added in order to obtain durable, dried potato products which are intended above all for consumption in the dry state. In the case of these products, dry products ground into powder or grits (as described in the first process type above), with or without addition of pure potato starch or cooked, dried potato products (as described with regard to the second process type), are placed into an extruder with addition of a small quantity of water, mostly some salt and suitable emulsifiers, whereby the mass becomes homogeneous and is heated as a result of the compressing effect of a compression extruder. A completely homogeneous, extremely tough dough develops and is extruded through a slit shaped or annular nozzle into a strip or some other form of a strand. This strip or strand is cut into small strips by a rapidly rotating knife. The cut pieces after cooling show a smooth to slightly irregular, rough surface; they are translucent and look like a completely homogeneous product.
These cut pieces represent an intermediate product. For final processing they usually are put in hot oil, in very hot air, or under an ultrared radiator. As a result of the sudden strong heating, the water still in the product is suddenly evaporated. Because of the extremely tough and extremely homogeneous structure of these products, the developed steam cannot escape. Steam bubbles develop, which expand the dough, so that a honeycombed, foamy, loose and crunchy structure develops with very low specific gravity, which can be consumed without any further processing.
The premise for the success of this process is a homogeneous cell and tearfree basic structure, so that the stream cannot escape before expansion to the outside. Microscopically, one can recognize a completely homogeneous mass with only a few individual cell fragments. No structures of grains of starch can be found any longer. Only by dying the preparation for example with iodine, is it possible to determine, that one is dealing with starch. No grains of starch are recognizable anymore, no matter whether swelled or unswelled, and no unhurt cell elements as well.
It has been suggested to obtain larger, cut resistance compact bodies such as dumplings/ball from durable dried potato products. In this case, one proceeds in such a way that dried products, as described above with regard to the first process type, are ground into a gritty powder, whereby powder from products, as described with regard to the second process type, can also be added partly. These mixtures must be wetted first of all with water at a ratio of 1 to 4 and they require a swelling time of 20 to 25 minutes. After that, a dumpling is formed from the strongly swelled mass, it is put in hot or boiling water, whereby a cooking time of between 20 and 30 minutes is required. The entire process, together with preparation time, consequently requires at least more than 50 to 60 minutes.
If one wishes to try to shorten the preparation time of dumplings made from such dried material and to put the products, as described with regard to the first and second process types, or the ground products (no matter whether in the shape of powder, granules or flakes) into a spherical pouch in order to obtain a dumpling by immersion of this pouch into hot or boiling water without previous swell time and deformation, then one will find the following results. Whenever pieces, cubes, slices or chips are put in such a pouch and this pouch is allowed to remain in boiling water until the contents are cooked and then the pouch is opened, the individual, reswelled, cooked pieces of potato drop out loosely and without connection, even if the pouch was filled tightly.
Whenever the coarse, powdery product, which after previous moistening until doughy, swelling time and deformation, resulting in a cut resistance dumpling in hot or boiling water, is put dry in such spherical pouches, and whenever these pouches are put into boiling or hot water, the border layers of the contents of the pouch are wetted rapidly. a mucous, jelly-like mass of 3 to 5 mm thicknes develops along the border layers of the pouch contents. The largest part of the contents of said pouch remains completely dry and powdery.
If, finally, flakes or porous granules, as described with respect to the second process type, are filled loosely into spherical pouches, then after placing of these pouches into hot or boiling water, the moisture will indeed penetrate to the inside of the pouch. However, a potato puree and not a dumpling will develop from these cooked dry flakes or granules. If the filling of the pouch is increased, then it is only the border layers of the contents again which are moistened with water after immersion of the pouch, and the largest part of the contents remains completely dry.
If one tries to fill the pouch perhaps with small cut, extruded pieces of a strip, as decribed with respect to the third process type, and allows the pieces to swell in hot or boiling water and thus possibly to obtain a compact dumpling, the resultant product is a tough, mucous, unshaped, unpalatable mass, which has little similarity to a dumpling.
In summary, for the preparation of dumplings from masses, the latter must be mixed or kneaded with a precisely measured quantity of water. Subsequently, these masses must rest for a certain time in order to swell. The real cooking time of the dumplings which follows is the same as in the case of dumplings customarily produced previously in the household.
Because of the precise dosing of the water that is to be added, it is furthermore generally necessary each time to use an entire package of the dried mass. For a household containing only one person, this method of preparation is unsuitable and relatively expensive.
Furthermore, a process for the production of a dried intermediate product from which so-called potato chips are made by putting the intermediate product in hot oil (British Pat. No. 998,603), also constitutes part of the prior art.
We should like to refer to German published application No. 1,049,685, British Pat. No. 603,074, as well as U.S. Pat. No. 2,954,295, as belonging to the further status of the prior art.
The dried products for making dumplings, known hitherto, consist partly of flour containing parts and partly of fibery parts mixed with the former, the fibery parts being grated. Partly, substantially boiled potatoes are processed on roll driers under suitable conditions of pressure in the vacuum into scaly dry products, which during processing, immediately swell into a more or less solid paste. Whenever these customary dried products are filled into a pouch or into some other receptacle permeable by water and are then put immediately into cold or boiling water in order to obtain a dumpling without mixing into a dough, then the border layers will swell quickly, are glued (pasted) together and constitute a dense wrapping jacket around the still dry particles on the inside; unfortunately, they cannot absorb any water whatever in this process. In this way, it is not possible therefore, to produce a dumpling by putting a dried product located in a pouch (into water).